title: Accumulation and effects of natural mixtures of persistent organic pollutants (POP) in Zebrafish after two generations of exposure.
abstract: Effects of exposure to environmentally realistic mixtures of persistent organic pollutants (POP) harvested from aquatic ecosystems in Norway were studied in an in vivo zebrafish model. POP were extracted from burbot (Lota lota) liver from two separate lakes, Lake Losna and Lake Mjøsa, and exposed to zebrafish through the diet in a two-generation study. Effects on survival, growth, sex ratio, and timing of puberty were investigated. In addition, the biomarkers 7-ethoxyresorufin O-deethylase (EROD) and vitellogenin (Vtg) were measured. The ratios of contaminant levels in extracts collected from Lake Mjøsa:Lake Losna were 6, 10, and 270 for polychlorinated biphenyls (PCB), dichlorodiphenyltrichloroethanes (DDT), and polybrominated diphenyl ethers (PBDE), respectively. The concentration range of POP measured in zebrafish was lower than in burbot originating from Lake Mjøsa, but comparable to concentrations previously reported in humans and wildlife. The results showed that exposure to environmentally realistic mixtures of POP exerted a negative effect on survival of fish in both generations. The marked drop in survival during 9-20 days post fertilization (dpf) suggested that this period may be a critical window for development. In both generations an earlier onset of puberty was observed and a higher proportion of males than females was noted in exposed fish compared to controls. Suprising effects of exposure were found on body weight. In the first generation (F(0)), body weight was significantly higher in both exposure groups compared to controls, while in the next generation (F(1)) the same exposures were associated with a decrease in body weight. Zebrafish exposed to relatively low quantities of POP showed a significant induction of biomarkers (EROD and Vtg), while fish exposed to higher exposure doses did not demonstrate induction.
authors.affiliation: Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, Oslo, Norway. vidar.berg@nvh.no
authors.forename: Vidar
authors.initials: V
authors.lastname: Berg
authors.forename: Jan L
authors.initials: JL
authors.lastname: Lyche
authors.forename: Camilla
authors.initials: C
authors.lastname: Karlsson
authors.forename: Benedicte
authors.initials: B
authors.lastname: Stavik
authors.forename: Rasoul
authors.initials: R
authors.lastname: Nourizadeh-Lillabadi
authors.forename: Nina
authors.initials: N
authors.lastname: Hårdnes
authors.forename: Janneche Utne
authors.initials: JU
authors.lastname: Skaare
authors.forename: Peter
authors.initials: P
authors.lastname: Alestrøm
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Lie
authors.forename: Erik
authors.initials: E
authors.lastname: Ropstad
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D003634:DDT / Q000032:analysis / Q000378:metabolism / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D004784:Environmental Monitoring; D005260:Female; D055768:Halogenated Diphenyl Ethers / Q000032:analysis / Q000378:metabolism / Q000633:toxicity; D008297:Male; D008954:Models, Biological; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000378:metabolism / Q000633:toxicity; D012737:Sex Factors; D012744:Sex Ratio; D012741:Sexual Maturation / Q000187:drug effects*; D014819:Vitellogenins / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism / Q000633:toxicity*; D015027:Zebrafish / Q000378:metabolism / Q000502:physiology*
chemical_list: D015415:Biomarkers; D055768:Halogenated Diphenyl Ethers; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D003634:DDT; D011078:Polychlorinated Biphenyls; D019363:Cytochrome P-450 CYP1A1